In vitro bioactivity, physical and mechanical properties of carbonated-fluoroapatite during mechanochemical synthesis

Mechanochemical synthesis method has been used to prepare nanocrystalline B-type carbonated fluoroapatite (B-CFA). Fourier transform infrared (FTIR) spectroscopy along with X-ray diffraction (XRD) technique was carried out to investigate the effect of milling time on the preparation of B-CFA. In vitro bioactivity of FA during synthesis was examined also by FTIR spectroscopy after soaking in simulated body fluid (SBF). Furthermore, the mechanical properties including hardness, fracture toughness, compressive strength, longitudinal modulus, Young's modulus, shear modulus and bulk modulus of the sintered samples, at 1000 and 1200 degrees C, for different milling times were measured by ultrasonic non-destructive technique. Furthermore, theoretical model is presented for FA according to the formula Ca-10(PO4)(6)F-2 center dot 18H(2)O. The QSAR properties including log P, total energy, heat of formation, energy gap, dipole moment, ionization potential, polarizability, molar refractivity and molecular weight were calculated. FTIR and XRD results revealed that single phase B-CFA was successfully formed after 9 h of milling. Moreover, the results also pointed out that the total energy of FA is much more than hydroxyapatite (HA) indicating that the structure of FA is more stable than HA. These results are in agreement with XRD ones for the sintered samples where they did not undergo decomposition reflecting its thermal stability.